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<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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</head>
<body>
    <ul>
        <li class="current">公告</li>
        <li>规则</li>
        <li>安全</li>
        <li>公益</li>
        <li>项目</li>
        <li>千牛</li>
    </ul>
    <div>
        <p class="current">公告内容</p>
        <p>规则内容</p>
        <p>安全内容</p>
        <p>公益内容</p>
        <p>项目内容</p>
        <p>千牛内容</p>
    </div>
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